We have set up a custom field of multi value type that gets the options from Database - > Category(Classifieds) -> name. Upon editing the user when we type a category name in that field, Server error is returned and the error log throws the error from the attached file.
We have tried to map the field to products and it worked perfectly. It looks like the same error we had when we tried to get the app working in the first place.
Log returns error when setting custom field to return category list